In fact, if what you want is a basic and easy to use fifo queue, slice provides all you need. queue := make([]int, 0) // Push to the queue queue = append(queue, 1) // Top (just get next element, don’t remove it) x = queue[0] // Discard top element queue = queue[1:] // Is empty … Read more
There are no such feature like retry attempts in RabbitMQ (as well as in AMQP protocol). Possible solution to implement retry attempts limit behavior: Redeliver message if it was not previously redelivered (check redelivered parameter on basic.deliver method – your library should have some interface for this) and drop it and then catch in dead … Read more
If you do not care about the data in management database; i.e. users, vhosts, messages etc., and neither about other queues, then you can reset via commandline by running the following commands in order: WARNING: In addition to the queues, this will also remove any users and vhosts, you have configured on your RabbitMQ server; … Read more
If you need to iterate over a queue then you need something more than a queue. The point of the standard container adapters is to provide a minimal interface. If you need to do iteration as well, why not just use a deque (or list) instead?
In traditional message processing, you apply simple computations on the messages — in most cases individually per message. In stream processing, you apply complex operations on multiple input streams and multiple records (ie, messages) at the same time (like aggregations and joins). Furthermore, traditional messaging systems cannot go “back in time” — ie, they automatically … Read more
Ben’s version is a stack instead of a queue, so i tweaked it a bit: NSMutableArray+QueueAdditions.h @interface NSMutableArray (QueueAdditions) – (id) dequeue; – (void) enqueue:(id)obj; @end NSMutableArray+QueueAdditions.m @implementation NSMutableArray (QueueAdditions) // Queues are first-in-first-out, so we remove objects from the head – (id) dequeue { // if ([self count] == 0) return nil; // to … Read more
Try using multiprocessing.Manager to manage your queue and to also make it accessible to different workers. import multiprocessing def worker(name, que): que.put(“%d is done” % name) if __name__ == ‘__main__’: pool = multiprocessing.Pool(processes=3) m = multiprocessing.Manager() q = m.Queue() workers = pool.apply_async(worker, (33, q))
For a producer/consumer thread, I’m not sure that ConcurrentLinkedQueue is even a reasonable option – it doesn’t implement BlockingQueue, which is the fundamental interface for producer/consumer queues IMO. You’d have to call poll(), wait a bit if you hadn’t found anything, and then poll again etc… leading to delays when a new item comes in, … Read more
Stack is a LIFO (last in first out) data structure. The associated link to wikipedia contains detailed description and examples. Queue is a FIFO (first in first out) data structure. The associated link to wikipedia contains detailed description and examples.
I guess the difference is in the contract, that when element can not be added to collection the add method throws an exception and offer doesn’t. From: http://java.sun.com/j2se/1.5.0/docs/api/java/util/Collection.html#add%28E%29 If a collection refuses to add a particular element for any reason other than that it already contains the element, it must throw an exception (rather than … Read more